The present invention relates to apparatus for use in collecting liquid samples, in particular biological samples, e.g. blood or saliva. Such apparatus is useful in collecting samples for use in diagnostic tests, and the invention also provides a kit for use in such tests.
Increasingly, use is being made of rapid diagnostic tests, both for use at home by a patient or for use by doctors in their surgeries. These tests have been made available through the use of diagnostic test devices and/or kits which provide everything needed to collect a sample and to perform the diagnostic test thereon. This enables many such tests to be performed more rapidly with less fuss and inconvenience. One example of such a test is the HELISAL.TM. test used to diagnose infection by H. pylori using a sample of blood.
Of course, such tests, and the test devices/kits provided to perform them, must be capable of providing the required level of accuracy that hospital laboratories can achieve, or at least a level of accuracy approaching that of hospital laboratories. In addition, it is often the case that the sample size required for the test fall within a particular range. For home use, and even for use by a doctor in the surgery, accurate measurement of sample volume may present problems. In addition, handling of samples which may represent a "biohazard" can be difficult. Thus, what is required is some form of apparatus which will allow collection of a sample in the right volume range, while at the same time minimising the risk of contact with the sample by the user.
In general, at present, samples are first collected and then transferred to a means, be it a device or the like or a simple test strip, where the test is performed. For example, to perform a test on a sample of blood, the person performing the test might prick the subject's finger and then use a simple capillary to draw up a sample of blood. This sample would then be transferred to the device or test strip for the reaction to occur. Clearly, it would be better if one could provide a sample collection apparatus which would accurately take up a "fixed" volume of sample and which would then release the sample in such a way that the sample is made available accurately and quickly every time, thus ensuring accurate and repeatable results.